Known examples of work vehicles include a gas-engine work vehicle, wherein a gas engine is installed in a work vehicle body, a handle base extends rearward from the work vehicle body, the handle base is provided with a hollow housing part for housing a cassette gas cylinder, a gas cylinder cover for closing the hollow housing part is provided, and the engine is driven by fuel gas supplied from the cassette gas cylinder, as is disclosed in Japanese Patent Application Laid-Open Publication No. 11-170876 (JP 11-170876 A), for example.
In the gas-engine work vehicle disclosed in JP 11-170876 A, a mouthpiece support for supporting a mouthpiece of the cassette gas cylinder is provided in the hollow housing part. This mouthpiece support is provided with a nozzle receiver for receiving an injection nozzle of the mouthpiece.
When the gas-engine work vehicle is not being used, the mouthpiece of the cassette gas cylinder is removed from the mouthpiece support, and the cassette gas cylinder is stored as removed from the hollow housing part. Therefore, it is believed that while the gas-engine work vehicle is being stored, dirt and other impurities enter the hollow housing part, and the entered impurities will penetrate into (adhere to) the nozzle receiver of the mouthpiece support.
As a countermeasure, a highly hermetic structure has been proposed for the entire hollow housing part.
However, the hollow housing part is a comparatively large space, and it is extremely difficult to make the entire hollow housing part into a highly hermetic structure. Therefore, there is a danger that dirt and other impurities will penetrate into (adhere to) the nozzle receiver (the mouthpiece support) while the work vehicle is in storage.